SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c24cc8bead188daff0bf9ccba24a2b3ba950b9bddce86e4ed3a4816c366aff6f' 
  AND token = 'Q058wnIef42G0gPLw27nAkcbZBMRTdr9MT0HQpPJ4/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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