SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '37900ed67d9ef6c26e30c1ef057d37d0a67cd816b6c3dfd3e8d13ee67c689755' 
  AND token = '75Zik2hjYqsw5KmdZrn1oSPCBlmjioWquga+XiVEGYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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