SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcae261ae9c90c96170db295701e25e3ca7ee85008a75a3ab27fe79ba677b0fe' 
  AND token = 'IeK7bQddKD7OSJCcCRx8zJeTdWMkRyR2PlgG5YiwOtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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