SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20a72fddbb6422af64a2c9d132cb32772b4136f65fb5237232cfaaf51f343988' 
  AND token = 'bT6/BgsQ14rqgJYvnBy8x1h5u64gUV2zr5rwBoPpcv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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