SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f77ae7c344380180aa80eead85b3ecf7431c2e068aedda4e81c19c16b89153ba' 
  AND token = 'AkQD53brhkIHeAePSeK47yry6SyFdsgW4DyJ13/B528=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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