SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9cf06d7b4596c0f856eb57cd39de715650643ac5b3ead6ff1b4d72455d316ee' 
  AND token = 'AwWYDnv/d49ZW9ZyV6ba4rWo8oEn3XxtpaBP7o/3N+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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