SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02e57f5754cd0b85675897228b3566064013be665cdd0223cd83472cc98b84fa' 
  AND token = 'Lhx/d5oHvtgo6ZSJEfIvErWYTqH0QoVx04z3mRzNwGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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