SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7236126d5b1df5688fe821e8edc06aed843ab56d347fe8ba1b36f6c72bc2b6be' 
  AND token = 'uYD3bFEzJ6L4k5rrpOjmlw+DOC2bnH4r+tuCogJaw+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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