SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da6e415fd82cc39fdda99c6a521100d0827c294732cc106ffb54363b00564895' 
  AND token = 'twmOeQqCsAJ6rrHt3frR3bduaBqnBUEMGn9q0Ek4kGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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