SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea24cf74d3d9415a3414580733a0dd37d48e6cffa010567fcfb32726bd20e52a' 
  AND token = 'lpJ8lGoQ/JnYBAWKnmC4LTQqk9D/owRp1YEbS4pxvJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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