SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2203519b2bdec87705f18a2a2e5454469943b08acd6f08daa286aa2d2217d05f' 
  AND token = 'fnpr9m8dB8iy2MbtEhhcFSWatE2x9fZVWm3BKfJjeME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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