SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c97e2f842c05afb4ff4440631ad23dbb07779c263435d34c09b506184b1a0f4' 
  AND token = 'dqZfnSCvUxzioDsTKfYUQWFYLzfhF45aRgYxgQGVKVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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