SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a69f1b3380c57476e0bbecab51ca2b29fa9e33192493d936040d61e154fe3e3' 
  AND token = 'ya5Ln7aUaCavT2eBtRSGml6fHaIbnzr4DQu+L4VAlQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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