SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5eb8c297ce8abe425a764051f96ed548487f2634be7198635c2fc2d1ffc289d5' 
  AND token = 'Vvn82WxIunBvMQjBam39JBiiY9JWxoQYHCrWdGKw6yU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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