SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ff98308e45b55ae1fca3edb606bc5b22699cc6c466355561bc2d425b0b51cf2' 
  AND token = 'XOVqJddC7TVBvcu3Sa342TYPjUbGi1VLBiRkW1Z5Nn8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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