SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '714fb61d1f49d6ca2d9ec28a2f413d059827ba27771361fa9c3ab06a244f44eb' 
  AND token = 'G5YQG3jrV6W1P5oGHLyDPG4mpz4qzTXfECwdSks6y1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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