SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f327244709a7157ae4cf68ea056ea060254b478236bc0b4539eb53cc1121a6d' 
  AND token = 'oaRZV/36Gpq2AvYchBYSvoCoVdduksxDnGSh8vQzFe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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