SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '78e77d67430b04556408a4b8f992fa86a5b8ae96c4909656148e3e5a1de82f02' 
  AND token = 'wRJfl6s+76xwwFrkUc0MERSIMmvSrdoMKntaoNmcIv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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