SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64c8ac767d3939156acb447091c0b60563c5c5d4f70f6b0e61fe7e74e868e4d1' 
  AND token = 'hd8Y6WKu/qJr+VD7GqBuTBn2G47ztKuneu/CCjs0gNo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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