SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0562135ff60b58779d742e14843555bb7083552e658c4588e77cd65acaf6dd9' 
  AND token = '+nFXeh7C1mmAQYR3o8om1XKezzX/8PQ/VoVjoDV3TJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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