SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af4c704646f56b3b806081273b2549bc0b3c99ec7851ffcb0439d94cede2bfac' 
  AND token = 'ZlhMwcxS1dMCC1J2CTXsEmuhQ3iFF1muhgsJIrYNo/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}