SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '980effbf374f4ddb381aa3f8f402079275e49b7c32388168c7a481a90b56366f' 
  AND token = 'ZbBERAhpilYY2DC4WJXJAzcGSgzGxoNkkfj8+5CNhAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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