SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c066de31fb8c1c11ac480573dade4eb18ea779ce198d67a4439a69aa06de5523' 
  AND token = 'Q5jX+KNIMh7vdZUr5yIVP9PB8Az8x5jX/HGB2Zz+B1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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