SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6cac67cce5edd8dfb48bf477a5e3480c99b9c5a867cd4f38dfbd626633fb852a' 
  AND token = 'Z1ISZVMYmVTXx/JiKXw1S7Cbxg+X41qjCZsqSizHNE8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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