SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61f63b5a01247dc4ecd6e5cdea02041f9163e723d2e61997464db4092bbb4e5b' 
  AND token = '1adXJ1vTNpuFMyf3QFZm2OMefW4+zpvzBb1+qqsIRe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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