SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfc1be47282226bf599ba14f16017eccaade63036be6b54a3ccdd0db8141e3c9' 
  AND token = 'HunQRvWPt9Exhk6mcwX7KNYqv4YohbwMw7InPyjBsQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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