SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2aef99f053834d01dcfdb3b92eb049405525cd8f1267267f9fb585ce0f28a35d' 
  AND token = 'subUVMqmIK0Omruw+H0mrqSsYm3fkCJxLworUjWxE70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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