SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a62be6d90e38206deed75429d4ca862f73a837e585652df9d23c78b1975ed9d' 
  AND token = 'bYvRguYqhkqIrCwsLCWNTyb0ERjkVUQkipwRXb9KIh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}