SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25c0084537fcaa6ff650da8aff55c77c184a30174742c4fe3b54d5553833708e' 
  AND token = 'o4ydgZPW6+hQ/vOzkfdq6/RZcUaKX2ehKdya2BOI8NY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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