SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e8110863a00cdd7377226f4b471857276bbc00bf5b637b49f2a21296dc0e40a0' 
  AND token = 'ghZQltf5NNRY/qAjJa/4+6NraV2h2SvTMXph09B6wdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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