SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10e31098d2d4c17101d8154b6b7ab6abf3c64241e50fdf27ed9dd0ace90efd8d' 
  AND token = 'TU8b/WBfG1d35ZMU1kZQ+KKi/rqHSzoZQdG2vtxnX1s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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