SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03a197d686a94b694742d4f991296eee10857afaefcb3dd92c4eb44c7c3d83be' 
  AND token = 'GMOA5C5DdaGk0YuLnRSj0+G1rEOUypmbQBp5Ayk4dLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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