SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a44289025f3805dbf175e68e2b8c174b33b3901488f081fa7fe062c7b87d716' 
  AND token = 'k9+Y1K0vwo/Ptf66aNrswVx8UdZPGueMwjg24Y/LICI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}