SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '806ab646bbed065189e7e9775e6dd43cb20805262764b1c5cf52168ffabd88ce' 
  AND token = '1q3Dou82rPAVLhyX4ERKacw+RgeB3wIdRxBw65tAnXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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