SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9dc941201b6dd91e0e37270d6d54e3076a84e50919fb5d7329881d2c5fc8764' 
  AND token = 'M6XroFcs4qVSYHrScqXh48WLyAsBQUUJMCvT+gGAH7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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