SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4f623b7e92fb74ba2476389750f75a84222c55c9196be2e1e23a08adb40ddea7' 
  AND token = 'hXxFD0tkKvV/b3WRoDqChodLxOHe2hhMbzgUmHkOsA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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