SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e69b9c951550ac280c7413f4f7146b83fa9e356e7d05c302aa0e14495ad35aab' 
  AND token = 'FlffBH5YiJJjuEfQfXUa5+5qvpnBDnlAa1PetuRKnco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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