SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80de2de0ac9f8a7f7501c2741ea5331d80eafc75d3c0996e1956dde31385b53b' 
  AND token = 'pjSGEo6/a5lpLRBei4FBUzxHB35ZbhsPjkf0kEo1eFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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