SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5daa534ebb5b1050d3d12a95cd8d5d3714bea4b4498cf561d81f009f9533dd79' 
  AND token = 'BLySyBuML4xviho/VcaREr9mU+Me8i6nxnei/1Tu4JY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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