SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '440c8301fa344df9ba80513d0f19bc2bc78e21962654765f71162b0f486413f1' 
  AND token = 'sff1nEq4basE3/Sj/v6KfM8zWvYtu/zYcdcoopYz39g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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