SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc967360dac56b0b607adab68f792f01c515f49ba46802a1a4ac4ea64f04bb8d' 
  AND token = 'ME1rQHyQt4yYSq/0D6P0wpYmbpN9bmr/aRkeAEB0aD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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