SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf2587b413652fc4d0b39486abcc78f1864c3a70dfe29376f6eb4673fbf85cff' 
  AND token = '08weeW+szhMEtCtPARnspsU1if58G01AVGQhIyEi4Ds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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