SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce7512dd214dc7253924542c7fc0010e8708ba6ec95b91da5ec8ac07a860e896' 
  AND token = 'LxLgJJQ5tIbK0jtygn+qoK2mY3Ud5U+byLPJlKONycQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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