SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7d5c68a67eeb5ba4e621b0e4ea754d4f838658f63fdc24327ca9740d3bf01b6' 
  AND token = 'xEgi+kKKXrCVJDdmX+kTIiowdhwP6vE4JFTETTDoXMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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