SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '938ab9d7f8cd303c6768fe7aa58a76d46e65ab3833250486ae00fc3f92cef37b' 
  AND token = 'qAbC8vx464qAm9BDWbDbdq+GFlHnI2NnJVUWnSX1wuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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