SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75e4f5b743c6041dbd94ae2de3586fc080553968d571064c437bb903749f0d60' 
  AND token = 'MdZlCyk2Mp+F0SqGE8YcxP0JIejjx5lRBm7FdWNKH4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}