SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e187010fd60f42ea05dd8afdfabed9b01cfab340f09454aaa01858c6fad2744e' 
  AND token = '3d5IQX+T4cdEceZ+0/9SQ4S51JaPIkQ23nHIuOaWsfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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