SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71817fd7fecba210c7da5603f36753fccafa76254670d8ebeece5b6485e0a7eb' 
  AND token = 'pqbuVm1Nwq4SzOsiwQD/eoQf15mvqJ3rYssKiaNOpGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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