SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c9f5b80257a67bf5f86bbde2915be46b3b32e6a7d0fe9b7e034227cfdf7840e5' 
  AND token = 'Bjj+glHMXzA8gnPbUR3o8HqBlVkZggQEY6zL5i1xshM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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