SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c679cfbf6a7bf6b57585db618d7b9a646a5388691e1999ff9cb7c77a79f2f70a' 
  AND token = '9ddgbsxIpS8JqWxsIhKwyYh2ZQkapvrFFKuYEHWRLpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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