SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4569c070d05939fa26908f890e746af9636a3760fb91a69cb2cde188d99bc3b8' 
  AND token = 'BDhK28nSGlBgHHoxiKNhRhera3Y/W+CAIFnGml+yp2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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