SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4da46088332854963b052b16dbd85b061f751928c43e82561942e9b4c0e5a85a' 
  AND token = 'BpJJcsqQcfIe/b1DdoDlkmvE0Q/ipkCqgbz2VopF/is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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