SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '106186f381a55522c3aeeb85d8d73b4411cfcf240d10c8368530fc756a46bc54' 
  AND token = 'zLqjHX1RP0g9YbQZfHd6CAedip7CzOilIRxdrpnf0KM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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