SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd45924e3a38c2c27b87b89824f1262f5d3a48f5fc95c5ed353ec352be1e52015' 
  AND token = 'yBhmY66L3mjjWcuPwNqD7maVohqTwstCe/zK9TkBkFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00082

JSON explain

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