SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85fb258c02ab25466aa6c87066bac0a06daa8e2ad546ea4da86b27ed76c48138' 
  AND token = '14Q8MfTSnuRd+5WzklfqAP9sHX0Cf6eq565lZKtxvFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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