SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdb754aab9628215e2e63e1ccca1c0ad450e566468f8a2144afcabdf589f0191' 
  AND token = 'e3tnh9gOOOkbHYdbtPRe2m9PEoun57G7wNcqRwx3NWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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