SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d9672fbd25375f0bf8c9ff6e82a16a9a8fcd1dc39c4f58765e5c2043323aa65' 
  AND token = 'ZrTJfdouHwfaeZG6djGHzYDC/FTSUJMAUyTrFSsFfgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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