SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aec187b712d4069a13597c1ccc6a09828e395024cfd3c9878fb5fe3425b35612' 
  AND token = 'e88NBvMU+liZeGMSO5dwE+iv8Lk4I3q/KBHrJBKtnKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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