SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32235fdd0627644a0675412fd419bdd68ff78e31031a6991e8fc1390332eb959' 
  AND token = 'tPCkP6mqXUtAuhHL5B/8FL+i1nS2xrxi4uNcjlwBOWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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