SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aea852623b610600eb3db95d1a3db2f961778d71e88a5f998510527f3d5fc75a' 
  AND token = 'Wi5Qnw8pd0JU6hgcfVPzgFw5kMVNEPs/rTdeEaV6zcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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