SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c95e188d992bbb1a9f3f8d53b411a2b6428a404deeb1983b35162d10246bef7' 
  AND token = 'qRV0SDPkK+lWqY1JpDnx4LvA4BP2YM7LLGt2XiFShmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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