SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1358232d7b3e90569929789f88f4f023bd1b97b5af283219f149428a3ef04d5' 
  AND token = '75mCBowkctbmwdX0ArHFsjqRsfc+vAXRIpGwESsYYKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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