SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b48d43fc58b54db8a7db70cbb5997fa1401d00b7711fc9c1b47fd8a6b21f672e' 
  AND token = '0XyF7nvoh6ZaYZHAZzdqSBKWItbhQAbWgFAnJDMxBAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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