SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bb0cfd628775804028210dbd9603bc5b9c0606be9654b2b7fac26aec74d4070' 
  AND token = 'YEX96oXRpHJo4Es2QSLrr+RV3SFGX3or+rr1gUvnfFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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