SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc147f231520a8ec9120a29134ca074310b418e81c84263839b1e06923989a7e' 
  AND token = 'QjFi/ck6R2CdzczrZJElVsrpVbVjXpnrz5FTKMJ0a44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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