SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54910509b45274602a9f48e24ace532be6d198fa17b2db99d3e733f6c4b5eb35' 
  AND token = 'mOvgm3qazFC8CxotXyWCcyGKn9YLPr+hgSwYcrdqp9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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