SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd44b6eeb9081b50201ec2002fbc50734c7ffe8b4ef211c4c7ab44eecfe2a459e' 
  AND token = 'Sjwj7JyqV/w+i85ov8WXmSuiJvY6ITlempzYoQ/r+3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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