SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7530ac2faf82b679466bdd5fc6773e0d6bbbe51ef7f47b4b6ddd2cf8181a3f70' 
  AND token = 'vi5kh/Zqem77F7jPc/6PtrOwlJVY0gXOA9BrbOF5XUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}