SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4118133a567b79747f6266fbdacf026bd7e286fc2b639529a2733c042c74dd95' 
  AND token = 'yPd4VpqbpOdkKVyvlnUlOC/uSGrBy9bGa53tW2t0PrU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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