SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '475b548bde96885f3af802c44fa590938e6c210dab7aa449114705183d96749a' 
  AND token = 'i/Q009y0BQ2o5b0u5cBJPR1aHpudn5C/7FyW4DBMKqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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