SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b05038e4e0ece29badc5c55a75caed63d082990020409c3bd11145f01d51b7c0' 
  AND token = 'Z1NxWHB/qOcIMSAF6ahjFU/8/hjAB7PFVrgHasJdQyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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