SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2253b836893d7a053159401fdb4cda4916e12ebc4097b438bafa531a72002f2' 
  AND token = 'REeeoWt+SZ5KGyVWBTY31ZZDwXXQ49endzXW4q3Tt+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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