SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf105fbd2a8b67b52fc2809aaf52eb177fa17189b5d3c5a74f74d897f60992b8' 
  AND token = 'W31Jy4ZouozM7xxYJCYzGDPydDcUVPUYtijwR2lB2SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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