SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a86625702d7a11b38fe27c0dd4003fb560cacd7f675275070272f34f95970973' 
  AND token = 'RrhoBxJk1C8FQ/SJAalDovhdSmCcrLJsz77xrwBAOT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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