SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e56bdfae38fc92514c7e3be23aff18ccfc49ae038cfd27d187e6b60a991f879' 
  AND token = 'LwZwJz5XQxpTslA1mIcS1TUtvPkogs0eCYtyBJmrvNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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